Apparatus for applying adhesive to corrugated sheets



J. T. FERARA 3,204,602 APPARATUS FOR APPLYING ADHESIVE TO CORRUGATED SHEETS Sept. 7, 19 65 2 Sheets-Sheet 1 Filed Jan. 14, 1965 FIGI.

4 5 INVENTOR JAMES T FERARA ATTYS.

J. T. FERARA APPARATUS FOR APPLYING ADHESIVE TO CORRUGATED SHEETS Filed Jan. 14, 1963 2 Sheets-Sheet 2 m m TOR JAMES T RARA ATTYS.

United States Patent 3,204,602 APPARATUS FOR APPLYING ADHESIVE T0 CORRUGATED SHEETS James T. Ferara, Atco, N.J., assignor to Samuel M. Langston Company, Camden, N.J., a corporation of New Jerse y Filed Jan. 14, 1963, Ser. No. 251,366

3 Claims. (Cl. 118-245) This invention relates to apparatus for applying adhesive to corrugated sheets and has for an object the provision of improvements in this art.

An object is to provide adhesive applying means which automatically controls the groove clean-out finger posi tion in accordance with the speed of the adhesive applying roll.

The improvements provided by the present invention are applicable to machines of a well-known type for making corrugated paperboard. These machines form a corrugated sheet, called the medium, and adhesively bond to the crests of the corrugations a smooth sheet which is called a liner.

The corrugated sheet is formed by passing a plain sheet between heated rolls having intermeshing axially extending tooth-like corrugations. In order to cause the corrugated sheet which is formed to separate from one corrugated roll and to follow the other corrugated roll for the application of adhesive to the crests of the corrugations, there are provided along the length of the corrugating rolls, say every two to three inches, a plurality of rib-like stripper members, each of which has one end or finger positioned within a circumferential groove formed in one corrugated roll and which closely encircles the other corrugated roll above the corrugated sheet carried thereon to hold it in position for the application of adhesive thereto, the terminal end of the stripper-retainer member extending past the adhesive applying position almost to the position where the liner sheet is applied to the adhesive coated corrugated sheet.

At the adhesive applying position a roll is employed for coating the crests of the corrugated sheet with adhesive. But since the retaining members extend out from the corrugated roll and sheet thereon it is necessary to provide grooves in the adhesiving applying roll to receive the retaining members.

Since the adhesive applying roll dips in the liquid adhesive in the pan in which it is held, the roll, especially in the grooves, takes up more adhesive than can be taken by the corrugated sheet. The excess adhesive on the cylindrical surface portions of the adhesive applying roll is removed by a metering or doctor roll which has all of the adhesive which is taken off the adhesive-applying roll scraped otf the back into the adhesive pan by a doctor blade.

It has also been the custom to remove excess adhesive from the grooves of the adhesive applying roll by curved cleanout fingers which extend beneath the doctor roll into the grooves of the adhesive applying roll near the nip of the rolls. By shifting these fingers up or down at their ends the amount of adhesive carried in the grooves can be regulated to accommodate for the viscosity of the adhesive and the speed of the adhesive applying roll. Since the viscosity can be maintained substantially constant, the adjustment is largely used to compensate for speed changes.

A difficulty in the operation of these machines has been that the adjustment of the fingers for speed change has been left to manual control and has often been neglected, with the consequence that much paper stock was spoiled by the application of too much or too little adhesive.

The objects of the invention as well as various features of novelty and advantages will be apparent from the following description of an exemplary embodiment thereof,

3,204,602 Patented Sept. 7, 1965 ice reference being made to the accompanying drawings, wherein:

FIG. 1 is a side elevation of apparatus embodying the invention;

FIG. 2 is an enlarged vertical sectional view through the apparatus;

FIG. 3 is an enlarged sectional view of parts shown in FIG. 2, some parts being omitted to show the finger operating mechanism;

FIG. 4 is a partial left side elevation of some of the parts shown in FIG. 3;

FIG. 5 is a partial enlarged horizontal section taken on the line 55 of FIG. 2;

FIG. 6 is an enlarged section taken in zone 6 of FIG. 2;

FIG. 7 is a section taken on the line 77 of FIG. 6; and a FIG. 8 is a diagrammatic view of finger shaft operating means providing for plural speed adjustments.

As shown in FIG. 1, a sheet 10, which is to form the corrugated sheet or medium 12, is fed in over several guide rolls 14, 16, 18 and 20 to and partly around a first corrugating roll 22. The first corrugating roll 22 meshes with a second corrugating roll 24, both usually heated, to corrugate the sheet 10 into a series of axial or longitudinal crests and valleys to form the corrugated sheet or medium 12. A plurality of arcuate shaped rib-like strippingretaining members 26 strip the corrugated sheet off the first roll 22 and retain it closely on the second corrugated roll 24 until after it passes an adhesive applying roll 28 which is part of an adhesive applying unit generally indicated by the numeral 30.

After adhesive has been applied to the crests of the corrugated sheet or medium, the medium is retained on the second corrugated roll 24 by the arcuate members 26 to pass through the nip between the corrugated roll 24 and a smooth roll 32 over which passes a smooth sheet 34 which adheres to form the liner. The smooth sheet 34 is taken from a supply roll or reel 36 and the united sheets are passed out over a roll 38 to a verticalconveyor and bridge conveyor.

As shown in FIG. 2, each arcuate member 26 has a peeler finger 40 which is disposed in a groove 42 of the first corrugating roll 22, the end of the finger extending almost to the nip between the two corrugating rolls 22 and 24 to peel the corrugated sheet or medium from the roll 22 and retain it on the roll 24. These rib-like members and the grooves in the roll 22 to receive them are located at distances of two to three inches apart along the length or axis of the corrugating rolls. They are relatively thin, say about 0.050" to 0.10".

The members 26 are adjustably supported upon an anchorage generally designated by the numeral 44 and are adjusted so as to closely overlie the corrugated sheet on the corrugated roll 24 except at a fluff-out zone 46 where the inner arcuate surface of the members 26 is relieved in an arcuate portion of smaller radius to allow the corrugated sheet to fluff out slightly at the adhesive line at the nip with the adhesive applying roll for better adhesive application. This zone is shown in enlargement in FIG. 6. Here it is also seen that the member 26 on its outer edge is bevelled as at 48, to permit easy access of each member 26 into the circumferential grooves in the adhesive application roll when the adhesive mechanism is returned to the adhesive applying position after being retracted from the operating position.

A metering or doctor roll 50 rotates reversely to the rotation of the adhesive applying roll 28 and sufficiently close to the surface thereof to strip off adhesive therefrom and leave a covering of adhesive of the desired thickness on the adhesive applying roll. At a distance from the nip between the rolls 28 and 50 the latter is provided with a doctor blade 52 to scrape the surface of the roll clean and ready to pick up adhesive from the roll 28 again.

An adhesive pan 54 is positioned below the rolls 50 and 28, the latter roll dipping in the adhesive in the pan at its lower edge and the doctor roll standing above the adhesive so as to have the adhesive which is scraped therefrom returned to the pan 54.

The pan is provided with a continuous flow of adhesive by way of a supply pipe 56 and an inlet with a baffle 58. The adhesive flows out over a weir 60 to a return passage and out by way of a return pipe 62.

Transversely adjustable dams 64 held in position on an edge of the pan by clamping devices 66 limit the supply of adhesive to the width of the corrugated sheet being handled. It is obviously undesirable to have the portions of the adhesive applying roll which do not apply adhesive to the corrugated sheet coated with adhesive because it would be thrown off on the bare part of the corrugated roll 24. The dam carries a roll wiper 67 of resilient material which bears against and seals off the ends of the adhesive applying roll 28, the wiper having sufiicient width to span a groove in the roll when the dam is located at a groove.

The adhesive applying roll 28 is provided with circumferential grooves 68 which embrace the rib-like members 26 which retain the corrugated sheet on the roll 24, a

narrow space being left on each side for adhesive to pass. In the nip space between the adhesive applying roll 28 and the doctor roll 50 there are disposed in the grooves '68 the ends of curved fingers 70 which extend adjacent the doctor roll 50 and are secured, as by screws 72 to mounting members 74. The mounting members 74 are adjustably secured, as by a split sleeve or hub 76 and clamping screws 78 to a transverse support shaft 80 which is turnably mounted in bearings of upstanding brackets 82 carried by the sides of the adhesive pan 54.

As shown in FIG. 3, the ends of the fingers 70 are adjustable in the grooves 68 by turning the shaft 80 on which they are mounted. Two positions of the end of a finger 70 are shown in FIG. 3, the lower full line position being for fast speed of the adhesive supplying roll 28 to allow less adhesive to be fed out to the corrugated sheet and the broken line position being for slow speed of the adhesive supplying roll to allow more adhesive to be fed out to the corrugated sheet.

Means are provided for shifting the finger position with respect to change in speed of the adhesive applying roll. As shown in FIGS. 3 and 4, the finger shifting means comprises arms 84 and 86 secured to the finger supporting shaft 80. A fluid operated device comprising a cylinder 88 mounted on a fixed support 90 and a piston in the cylinder having a piston rod 92 engaging the arm 86, operates the shaft in one direction; and a fluid operated device comprising a cylinder 94 mounted on the support 90 and a piston in the cylinder having a piston rod 96 engaging the arm 84 operates the shaft in the other direction. An adjustable stop in the form of a set screw 98 threaded in a lug 100 of the cylinder 94 and having a lock nut 102 limits the return movement of the arm 84 when the shaft is turned by the piston rod 92; and a set screw 104 threaded in a lug 106 of the cylinder 88 and having a lock nut 108 limits the return movement of the arm 86 when the shaft is turned by the piston rod 96.

The means for controlling the action of the cylinders 88 and 94 is shown diagramatically in FIG. 3. For low speed up to about 150 to 200 feet per minute the switch S is open and the solenoid 110 is not energized and the spring-urged valve 112 supplies pressure fluid to slow speed cylinder 88 to hold the fingers 70 up in slow speed position. Above the pre-set low speed limit the switch S is closed to energize solenoid 110 and shift the valve 112 to supply fluid to the high speed cylinder 94 to lower the end of fingers 70 to high speed position.

The operation other than explained above will be understood without further description. It is seen that means 4 are provided for shifting the fingers automatically for different speed conditions.

In FIG. 8 there is shown an arrangement which provides adjustment of the finger 70 for a plurality of different speeds above a low speed range. A spring (or a cylinder, if desired) has a constant pressure applied which is just sufiicient to overcome gravity and hold the fingers in a raised low speed position. The spring at one end abuts a fixed stop 122 and is carried on the end of a rod 124 which passes therethrough. The rod in turn is connected to one arm of a bell-crank member 126 secured to the shaft 80, movement of said member being limited in a counterclockwise direction under bias of the spring by a stop 128.

The other arm of the member 126 overlies a bank of fluid cylinders 130, 132 and 134 having pistons of uniform stroke. It will be obvious that cylinder when operated will adjust the fingers to a first speed change condition and subsequent speed changes may be correspondingly compensated for by activating the cylinders 132 or 134. If desired, cylinders which act at the same arm length but with piston rod stops located where they will stop the piston movement at different points may be used.

It is thus seen that the invention provides adhesive appying apparatus wherein groove clean-out fingers are provided together with means for adjusting the position of the fingers in accordance with speed to supply the proper amount of adhesive in the grooves of the adhesive applying roll.

While certain embodiments of the invention have been described for purposes of illustration, it is to be understood that there may be various embodiments and modifications within the general scope of the invention.

I claim:

1. Apparatus for applying adhesive to corrugated sheets comprising in combination, a corrugated roll carrying a corrugated sheet thereon, axially spaced arcuate rib members holding the corrugated sheet on the corrugated roll, an adhesive applying roll having a surface for applying adhesive to the crests of said corrugated sheet and grooves receiving said arcuate rib members, a doctor roll operating adjacent the surface of said adhesive applying roll, an adhesive holding pan in which the lower part of said adhesive applying roll dips, adjustably mounted cleanout fingers mounted above the rolls in said pan with their ends disposed in the grooves of said adhesive applying roll at the nip with said doctor roll for metering the amount of adhesive supplied by said grooves, and means to shift the position of said fingers to different vertical positions in said grooves to change the amount of adhesive applied at said grooves to said corrugated sheet.

2. Apparatus for applying adhesive to corrugated sheets as set forth in claim 1, wherein said fingers are mounted on arms on a turntable shaft for vertical adjustment of the ends of the fingers, means urging said arms and fingers in opposite directions, the means urging said fingers in one direction acting constantly and the means urging the arms and fingers in the opposite direction being selectably operable to suit different operating conditions.

3. Apparatus as set forth in claim 2, wherein said means for urging the arms and fingers in the opposite direction comprises a plurality of power elements provided with stroke limiting means for different arm and finger posi' tions.

References Cited by the Examiner UNITED STATES PATENTS 1,106,502 8/14 Ferres 156473 1,558,271 10/25 Newell 118--259 X 2,711,206 6/55 Shields 156-473 2,797,661 7/57 Learning.

2,830,555 4/58 Barrett 1187 3,046,935 7/62 Wilson 118261 X CHARLES A. WILLMUTH, Primary Examiner. RICHARD D. NEVIUS, Examiner. 

1. APPARATUS FOR APPLYING ADHESIVE TO CORRUGATED SHEETS COMPRISING IN COMBINATION, A CORRUGATED ROLL CARRYING A CORRUGATED SHEET THEREON, AXIALLY SPACED ARCUATE RIB MEMBERS HOLDING THE CORRUGATED SHEET ON THE CORRUGATED ROLL, AN ADHESIVE APPLYING ROLL HAVING A SURFACE FOR APPLYING ADHESIVE TO THE CRESTS OF SAID CORRUGATED SHEET AND GROOVES RECEIVING SAID ARCUATE RIB MEMBERS, A DOCTOR ROLL OPERATING ADJACENT THE SURFACE OF SAID ADHESIVE APPLYING ROLL, AN ADHESIVE HOLDING PAN IN WHICH THE LOWER PART OF SAID ADHESIVE APPLYING ROLL DIPS, ADJUSTABLY MOUNTED CLEANOUT FINGERS MOUNTED ABOVE THE ROLLS IN SAID PAN WITH THEIR ENDS DISPOSED IN THE GROOVES OF SAID ADHESIVE APPLYING ROLL AT THE NIP WITH THE SAID DOCOTR ROLL FOR METERING THE AMOUNT OF ADHESIVE SUPPLIED BY SAID GROOVES, AND MEANS TO SHIFT THE POSITION OF SAID FINGERS TODIFFERENT VERTICAL POSITIONS IN SAID GROOVES TO CHANGE THE AMOUNT OF ADHESIVE APPLIED AT SAID GROOVES TO SAID CORRUGATED SHEET. 